1. Field of the Invention
This invention relates to processing apparatus for a signal processing network comprising a plurality of interconnected processing units for real time signal processing.
2. Description of the Prior Art
The invention finds particular application for audio signal processing in, for example, an audio mixing console.
Traditionally, audio mixing consoles have been based on discrete technology with audio signal processing modules connected together in a desired relationship and then controlled by manually operable switches on the console. It has been a relatively straightforward task, albeit a skilled and time consuming task, to oversee the physical interconnections necessary during setting up and debugging a desired audio processing structure. However, traditional audio mixing consoles have a number of disadvantages including their physical size, the total number of manually operable controls (fader, potentiometers, switches, etc.), and the relative inflexibility of the overall arrangement.
Accordingly, it has been proposed to provide an audio mixing console comprising a front panel including a plurality of user operable controls for controlling different audio signal processing functions and a digital signal processor for processing audio signals in response to the settings of the user operable controls. It is hoped that such technology can lead to reductions in the overall size of such consoles while at the same time increasing flexibility.
However, in order to be able to process digital audio signals in real time, a highly parallel signal processing structure is required. A problem with the use of a highly parallel processing arrangement for the processing of signals in real time is the scheduling of tasks between the processors and ensuring that the tasks are performed in the correct sequence to avoid, for example, race conditions or signal data, corruption.